Your Mum may have told you to keep your head warm as you lose heat through the top of your head. This also goes for your house. Around 45 per cent of heating and cooling can escape through the roof, according to the Department of Industry.

If you live in in a hotter climate and have a verandah roof, this should also be insulated to reduce the heat from the sun warming up your house.

Walls

You can also insulate the sides of your house for a 20 per cent reduction on heating and cooling costs.

This is of value no matter what climate you live in, unless of course, your house is made from straw bale or autoclaved aerated concrete.

Wall insulation can be retrofitted if your house is not already insulated or if your current installment is not sufficient to keep your house cool in summer or warm in winter.